Exam P topic · 23–30% syllabus weight

General Probability

Independently written solutions mapped to this official syllabus topic. Pages appear only after all required checks agree.

Topic orientation

What this topic tests

General Probability connects event algebra, conditional probability, independence, counting, and Bayes’ theorem. The main work is usually translating a verbal experiment into events whose intersections and complements can be calculated cleanly.

Exam questions often hide the decisive denominator or conditioning event inside the setup. A strong solution names the event first, checks that the pieces form a valid probability model, and only then substitutes numbers.

Typical failure modes

Using an unconditional probability where a conditional denominator is required
Treating mutually exclusive events as independent
Forgetting a complement or double-counting overlapping cases

Published ledger

Verified solutions

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